Fungicidal composition comprising a 4, 5-pyrazoledione-4-oxime



Patented 5. 1950 FUNGICIDAL COMPOSITION COIWPRISIN G A4,5-PYRAZOLEDIONE-4-OXI1HE Byron A. Hunter and Norman K. -Sundholm,Naugatuck, Conn., assignors to United States Rubber Company, New York,N. Y., a corporation of New Jersey No Drawing. Application February 12,1947, Serial No. 728,194

10 Claims.

This invention relates to new and useful improvements in fungicides. Theinvention further relates to methods of treating plants, and to methodsof protecting organic material subject to attack by microorganisms, asthe immunizing of seed, and the mildewproofing of fabrics and othermaterial.

We have found that 4,5-pyrazoledione-4-oximes are effective fungicides.The structure of these compounds may be represented by the formula:

wherein R1 and R2 may be hydrogen, or an aliphatic radical, or anaromatic radical. Examples of 4,5-pyrazoledione-4-oximes are:

4,5-pyrazoledione-4-oxime 1-methyl-4,5-pyrazoledione-4-oxime3-methyl-4,5-pyrazoledione-4-oxime 3-ethyl-4,5-pyrazoledione-4-oxime3-propyl-4,5-pyrazoledione-4-oximel,3-dimethyl-4,5-pyrazoledione-4-oximeB-ethyl-1-methyl-4,5-pyrazoledione-4-oxime1-phenyl-3-butyl-4,5-pyrazoledione-4-oxime1,3-diphenyl-4,5-pyrazoledione-4-oxime 1- (4-chlorophenyl) -3-methyl-4,5-pyrazoledione 4-oxime 1- (4-methoxyphenyl) -4,5-pyrazoledione-4-oximeThe preparation of the 4,5-pyrazoledione-4-oximes is well known. Ingeneral, they are formed by the reaction of nitrous acid on thecorresponding 5-pyrazolone, which is prepared by reacting hydrazine or amonosubstituted hydrazine with a p-keto ester. They can also be preparedby reacting the isonitroso-p-keto ester with hydrazine or a substitutedhydrazine.

The 4,5-pyrazoledione-4-oximes may be used as seed protectants anddisinfectants, and to protect plants, which term includes plant parts,or soil from microorganisms harmful to seeds and plants. They may alsobe applied to prevent or retard fungus growth and the formation ofmildew on organic material, such as wood, fur, rope, hair, feathers,cotton, wool, synthetic organic fibers, and the like. They may beapplied as a dust, as in admixture with a powdered solid carrier, suchas clay or talc, or they may be applied as a liquid or spray in a liquidcarrier, as in solution in a suitable solvent, or suspended ma suitablenon-solvent, for example, water.

Preferably when applied in aqueous suspension,

the composition contains a. dispersing agent for the chemical. In seedtreatment, the 4,5-pyrazoledionel-oximes are preferably applied to theseed, as by tumbling with the chemical admixed with a powdered solidcarrier. In foliage treatment, the 4,5-pyrazoledione-4-oidmes arepreferably applied to the plant parts by spraying with an aqueoussuspension of the chemical containing a dispersing agent. The chemicalsmay be applied to foliage by the aerosol method. Solutions for theaerosol treatment may be prepared by dissolving the chemical directly inthe highly volatile liquid carrier or first dissolving the chemical in aless volatile solvent and then admixing such solution with the highlyvolatile liquid aerosol carrier. The 4,5-pyrazoledione-4-oximes may beused admixed with carriers that are active of themselves, for example,other fungicides, or bactericides, insecticides, insectifuges,fertilizers, hormones.

The examples below showing the effectiveness of various4,5-pyrazoledione-4-oximes as fungicides are given to illustrate theinvention.

The 1 phenyl 3 methyl 4,5 pyrazoledione 4 oxime tested in the examplesbelow was prepared as follows: A solution of 17.5 g. (.1 mol) ofl-phenyl-3-methyl-5-pyrazolone in a mixture of 9 cc. of concentratedhydrochloric acid and 40 cc. of water was cooled and stirred in amixture of ice and water. 'A cool solution of 7 g. of sodium nitrite in15 cc. of water wasadded slowly. An orange solid separated. The mixturewas stirred for one-half hour. The solid product was removed byfiltration, washed with water, and recrystallized from alcohol. Theproduct had an orange color and melted at 158 C. Knorr (Berichte17,2042) gave a melting point of 157 C. The 1- (4-ch10ropheny1)-3-methyl-4,5-pyrazoledione-4-oxime, m. p. 182-183 0., was preparedsimilarly. Chattaway and Strouts (Journal Chemical Society (London) 125,2426) gave a melting point of C. The 1,3-diphenyl-4,5-pyrazoledionel-oxime, m. p. 203 C., was prepared similarly. Sachs andBecherescu (Berichte 36, 1135) gave a melting point of 200 C. The3-methyl-4,5-pyrazoledione-4-oxime, m. p. 237 C., was preparedsimilarly. Wolff (Berichte 37, 2832) gave a melting point of 232 C.

Example I The various 4,5-pyrazoledi0ne-4-oximes were sprayed on tomatoplants in the form of aqueous suspensions of the chemicals at a dosageof 2000 parts per million (I p. m.) The aqueous suspensions of thechemicals contained a small amount plants were sufficiently dried, thethus treated plants, together with untreated (check) plants, wereuniformly inoculated by spraying onto the foliage an aqueous suspensionof spores of Alternaria solani, the fungus responsible for a seriousblight disease of this crop. The plants were placed in an inoculationchamber at 75 F. and 99% humidity for 20 hours, after which they wereremoved to normal greenhouse conditions. After 48 hours in thegreenhouse. the eflfectiveness of the various 4,5-pyrazoiedione-4-oximeswas determined by counting the .blightlesions on the tomato plantstreated with the various 4,5-pyrazoledione-4-oximes, and comparing withthe number of blight lesions on the check plafilts which were nottreated with the chemicals. percent control by the various4,5-pyrazoledione- 4-oximes is shown in the following table:

Treatment Chemical Control 1 ldi -4 xi P" 37 l-Phen l-3-methy-4,5-pyrazoe on -0 me l-(p-OlfiorophenylH-meth14,5-pyrazoledione4-oxime... 99 l,3-Digheuyl-4,5-pyrazol oue-4oxime 83z-Met yl-4,5-pyrazoledlone-4-oxime 93 Example II Alternaria ScleratiniaChemical aolani america'na Phen l-3-meth i4 5- azoiedione- P. P. M. P.P. M. 4-oxi ie.... l u 100 100 l-( Ohloro eny met y pyl l i g H g: It lle 1 100 en azoe 0n 'oxime. f..s 1,000. 1,000

Having thus described our invention, what we claim and desire to protectby Letters Patent is:

1. A fungicidal composition comprising an aqueous suspension ofa'4,5-pyrazoledione-4-oxime, in which the nitrogen in the 1-position isattached to a member of the group consisting of hydrogen and arylradicals and the carbon in the 3-position is attached to a member of thegroup consisting of alkyl and aryl radicals, said aqueous suspensioncontaining a dispersing agent.

2. A fungicidal composition comprising an aqueous suspension of a1-aryl-4,5-pyrazoledione- 4-oxime, said aqueous suspension containing adispersing agent.

3. A fungicidal composition comprising an aqueous suspension of1-phenyl-3-methyl-4,5-pyrazoledione-4-oxime, said aqueous suspensioncontaining a dispersing agent,

4. A fungicidal composition comprising an aqueous suspension of1-(p-chlorophenyl) -3- methyl-4,5-pyrazoiedione-4-oxime, said aqueoussuspension containing a dispersing agent.

5. A fungicidal composition comprising an aqueous suspension of1',3-diphenyl-4,5-pyrazoledione-4-oxime, said aqueous suspensioncontaining a dispersing agent.

6. A fungicidal composition comprising 9,4,5- pyrazoledione-4-oxime inwhich the nitrogen in the 1-position is attached to a member of thegroup consisting of hydrogen and aryl radicals and the carbon in the3-position is attached to a member of the group consisting of alkyl andaryl radicals, said composition containing a surfaceactive dispersingagent.

7. A fungicidal composition comprising a 1-ary1-4,5-pyrazoledione-4-oxime and a surfaceactive dispersing agent.

8. A fungicidal composition comprising alphenyl-3-methyl-4,5-pyrazoledione-4-oxime and a surface-activedispersing agent.

9. A fungicidal composition comprising l-(pchlorophenyl) 3 methyl 4,5pyrazoledione-4- oxime and a surface-active dispersing agent.

10. A fungicidal composition comprising 1,3-diphenyl-4,5-pyrazoledione-4-oxime and a surface-active dispersingagent.

' .HUNTER.

NORMAN K. SUNDHOLM.

REFERENCES CITED The following references are of record in th file ofthis patent:

Knorr: Berichte, vol. 17, page 2042.

Chattaway and Strouts: Journal Chem. Soc. (London) ,vol. 125, page 2426.

Sachs and Becherescu: Berichte, Vol.36, page 1135. i

Wolff: Berichte, vol. 3'7, P e 2832.

1. A FUNGICIDAL COMPOSITION COMPRISING AN AQUEOUS SUSPENSION OF A4,5-PYRAZOLEDINE-4-OXIME, IN WHICH THE NITROGEN IN THE 1-POSITION ISATTACHED TO A MEMBER OF THE GROUP CONSISTING OF HYDROGEN AND ARYLRADICALS AND THE CARBON IN THE 3-POSITION IS ATTACHED TO A MEMBER OF THEGROUP CONSISTING OF ALKYL AND ARYL RADICALS, AND AQUEOUS SUSPENSIONCONTAINING A DISPERSING AGENT.